The playback process of MPEG-2 compressed video data includes determining the order and the times to display individual pictures. MPEG-2 is characterized by varying degrees of compression that take varying amounts of time to decode. Additionally, pursuant to MPEG-2, the data dependencies that are defined and permissible between pictures create situations where the pictures are decoded in a different order from the display order.
To assist with displaying the pictures at the correct times, the encoder writes a parameter known as the presentation time stamp, indicating the time that the picture is to be displayed. The foregoing works, provided that the vertical synchronization pulse is aligned with the start of frame. However, the timing of the vertical synchronization pulse is a function of the instant that the display device is powered on. Accordingly, the foregoing assumption cannot be assured.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of ordinary skill in the art through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.